Thoracic outlet syndrome (TOS)

Thoracic outlet syndrome is a rare condition that involves pain in the neck and shoulder, numbness and tingling of the fingers, and a weak grip. The thoracic outlet is the space thoracic outlet syndrome symptomsbetween your collarbone and your first rib. This area is loaded with nerves, muscles, and blood vessels. If your shoulder muscles are too weak to stabilize the collarbone in place, it may slip down and forward, putting pressure on the nerves and blood vessels that lie under it.

Thoracic outlet syndrome is a combination of three related syndromes. The first form called the neurogenic form, involves the compression of the brachial plexus, which is a collection of nerves in the neck and armpit. The second form is a vascular form involving compression of the subclavian artery or vein, which are the major blood vessels of the upper chest. The last form is a non-specific or disputed TOS, in which there is no neurological deficit but patients experience neurological symptoms and pain. This is the most common form.
Thoracic outlet syndrome can result from injury, disease, or a congenital problem, such as an extra rib above the first one, or an abnormal tight band connecting the spine to the ribs.
Blood vessels and nerves coming from the spine or major blood vessels of the body pass through a narrow space near your shoulder and collarbone on the way to the arms. Sometimes, there is not enough space for the nerves to pass by or through the collarbone (clavicle) and upper ribs.
Pressure (compression) on these blood vessels or nerves can cause symptoms in the arms or hands. Problems with the nerves cause almost all cases of thoracic outlet syndrome.
Thoracic Outlet Syndrome symptoms may include:
• Pain, numbness, and tingling in the pinky and ring fingers, and the inner forearm
• Pain and tingling in the neck and shoulders
• Signs of poor circulation in the hand or forearm
• Weakness of the muscles in the hand
• Difficulty with overhead activities due to compression of nerves
• Limited range of motion of shoulder

Physical therapy is often used to treat thoracic outlet syndrome. It helps:
• Strengthen muscles of the shoulder to help support the collarbone.
• Improve your range of motion in the shoulder
• Promote better posture, to help standing and sitting straighter, which lessens the pressure on the nerves and blood vessels.
Most people with thoracic outlet syndrome can have complete resolution of symptoms with conservative measures, including exercises specific for thoracic outlet syndrome, physical therapy, and avoiding stressing the tissues of the thoracic outlet. It can be helpful to avoid sleeping with the arms extended above the head. Rarely, surgical intervention can be necessary to take pressure off of involved nerves and blood vessels.


PubMed Health: The Cochrane Collaboration. Published by John Wiley & Sons, Ltd 2010
PubMed Health: A.D.A.M. Inc. 2013
AAOS: American Academy of Orthopaedic Surgeons: OrthoInfo